The present invention relates to bearing lubrication and more specifically to the lubrication of bearings at startup of a machine utilizing the bearings (machine startup).
Bearings in rotating machinery usually require some type of lubricant to ensure long life and proper function. Bearing lubrication is critical, especially in applications where the bearings experience high speeds, high loads, and/or high temperatures, such as in aircraft electrical power generators. In aircraft electrical power generators and similar applications, a pump delivers lubricating fluid supply from a lubrication reservoir to the bearings. During machine startup, lubricant delivery to the bearings may take some time as the pump pressurizes the lubricating fluid, resulting in the bearings rotating with insufficient lubrication for a period of time. Whenever the bearings rotate at machine startup without sufficient lubrication, the bearings experience a significant amount of wear. It is therefore critical to deliver lubrication to the bearings as soon as possible during machine startup so as to reduce bearing wear.